1. Technical Field
The present invention relates to a method for manufacturing wiring substrates and a method for manufacturing electronic devices.
2. Related Art
A subtractive method and an additive method are known as a method for forming wirings on a flexible substrate. In the subtractive method, a metal layer is formed over the entire surface of a flexible substrate, a photoresist is formed on the metal layer by patterning, and the metal layer is etched by using the photoresist as a barrier. In the additive method, a photoresist is formed on a flexible substrate by patterning, and a metal layer is deposited by a plating process in an opening section in the photoresist.
These methods entail problems concerning consumptions of resources and raw material, in view of the fact that the photoresist is finally removed, and further in view of the fact that a part of the metal layer is removed in the subtractive method. Also, they require the steps of forming and removing a photoresist, which results in a problem of a large number of manufacturing steps. Furthermore, because the measurement accuracy of wirings depends on the resolution of a photoresist, there is a limit in forming wirings at a higher level of accuracy.
It is an object of the present invention to deposit a metal layer only in a required portion, and form wirings with a simple manufacturing process.